摘要
脂肪和脂肪酸的代谢及生理功能都与甘油三酯的结构有关,甘油三酯在消化过程中通常是1,3位的脂肪酸首先被胃酶和胰酯酶水解下来形成2-单甘油酯和游离脂肪酸,2-单甘油酯可以直接吸收、酯化成为甘油三酯。母乳中的棕榈酸大多结合在甘油三酯的2位上,而婴儿配方乳粉中的棕榈酸多结合在1,3位置上。植物油和婴儿配方奶粉中结合在1,3位置上的棕榈酸不易吸收,易形成不溶性的皂化钙随粪便排出体外,导致能量和钙的流失。
The structure of TAG may be used as a biological reference point because the structure of TAG influences the metabolism of fat and its component fatty acids. Triacylglycerol digestion involves hydrolysis of fatty acids esterified at the glycerol 1,3 positions by gastric and pancreatic lipase to produce 2 - monoacyglycerols and unesterified fatty acids, which are then absorbed and re- esterified into triacylglycerol. Palmitic acid （16：0） is predominantly esterified to the 2- position of human milk triacylglycerol but to the 1,3 position in the oils used in infant formulas. Palmitic acid esterified at sn - 1 and 3 positions of the glycerol backbone, as is the case in vegetable oil and in most infant formulas, was shown to be poorly absorbed and be secreted into feces as insoluble calcium soaps, leading to loss of both fatty acids （energy） and calcin.
出处
《中国粮油学报》
EI
CAS
CSCD
北大核心
2009年第5期80-83,共4页
Journal of the Chinese Cereals and Oils Association
关键词
甘油三酯
棕榈酸
结构
营养吸收
TAG, palmitic acid, structure, nutrition absorb
